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LT77 Gearbox Identification

Just picked up an LT77-type 'box this afternoon for a price too good to miss. I'm a bit stuck as to identification though - the number on the machined metal surface doesn't start with the usual 'GxxA' code - instead I have 'CL' then a series of digits followed by the letter 'C'. Guess this might be the Triumph variant ? anyone shed any light on the ratios ??

Pete.

My next engine will have a capacity in cubic inches equal to my Forum post count !!!

RE: LT77 Gearbox Identification

Pete,

That'll be a TR7 box, not to familiar with their spec I'm afraid. Things like input shaft length, clutch bearing support shaft etc could be different (the rest doesn't really matter) and I can't cross reference the part numbers.

RE: LT77 Gearbox Identification

Cheers Russ - yes at £40 it was too good an opportunity to pass up! Seems to be in good nick as there is very little play on the input shaft. Don't suppose you have a regular LT77 hanging about you could take a couple of dimensions off so as I can check to see if the input shaft lenght is same/different? Thought it could be a good bet for a rebuild as coming from a Triumph it would never have seen very much torque !! Whipped the 'front cover' off & what I can see of the bearing surfaces look in good nick - but there is the usual pinch of swarfe stuck to the magnet though !

Pete.

My next engine will have a capacity in cubic inches equal to my Forum post count !!!

RE: LT77 Gearbox Identification

Cheers Russ,

BTW I'm just getting over my 2nd load of bugs since 1st Jan. Had a cold which lasted a few days back then & now have been off work with the good old 5 day flu !! - Personally I blame the Yanks with their juice-guzzling ironmongery for causing all this Climate Change stuff..

Pete.

My next engine will have a capacity in cubic inches equal to my Forum post count !!!

RE: LT77 Gearbox Identification

...Interestingly, Rimmer Bros list exactly the same part no in their catalogue for the TR7/8 5-speed as they do for the SD1 'box - so I recon that I'm probably onto a winner !! (we shall see...)

Russ, could you help shed a bit of light on the issue of the 'D' suffix 'box being 'the strongest' as is often read - also when a reconditioner such as Rimmers offer a 'heavy duty' LT77 what specific modifications would they have possibly made ? I belive that RPI were once replacing the tapered roller bearings with a standard bearing claiming that this improved the 'strength'.

Pete.

My next engine will have a capacity in cubic inches equal to my Forum post count !!!

RE: LT77 Gearbox Identification

Hi Pete Yes the box you have is the same as on the SD1, there are no differances other than one thing, which Rimmers gave me duff info on, and that is that the pivot pin is a different length, so make sure that you change the pivot pin, other wise everything else will fit ( of course the bell houseing is different as well ) but I'm sure you already figured that one out. :7 :7 :7

RE: LT77 Gearbox Identification

Thanks Martin,
Yes looking at the Rimmer website, it seems that all the 'late type' Triumph boxes are internally identical to the A/B/C Suffix rover SD1 boxes. This is great as mine is of this type & has only seen a poxy 2 litre Triumph motor attached to it up till now ! - 4.6 litres should be a nice wake-up call ! Plan to strip & inspect but probably will do the minimum as it looks in good nick. All this for £40 and a Triumph Bellhousing too !

Pete.

My next engine will have a capacity in cubic inches equal to my Forum post count !!!